My electric shower broke and i got anew one to replace it. the installation is simple, but the electrical wires are about an inch too short for their new ports. there is no slack in the cable to pull more out of the wall. can i get new bits of wire to extend them and cover the joins with insulation tape, or is this likely to cause my death next time i have a shower?! if i can't do this, if there anything i CAN do other than rewiring my bathroom? thanks

Other than changing like for like which this of course is not as cables don't fit it will come under Part P and the Local council is likely to charge you as much to DIY as a registered electrician will charge for whole job so not worth doing. With added dangers to yourself with any errors I would not think worth your while to DIY.
Eric

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